Another study carried out in homes under ‘real-use’ conditions found that e-cigarettes did increase the airborne nicotine in homes, but homes with combustible cigarette smokers had 5.7 times more airborne nicotine.

A third experiment, carried out in lab conditions found that similar levels of serum cotinine (which is used to measure nicotine) in people exposed to combustible cigarette smoke and those exposed to electronic cigarettes.

This final group of researchers concluded that short-term exposure to electronic cigarettes did not elicit a reduction in lung function or an increase in inflammation, which has been linked to cardiovascular disease. Volunteers that were exposed to second hand smoke from combustible cigarettes did experience these two negative functions.

Most of the studies concentrate on nicotine because this is one of the key byproducts released from e-cigarettes. It is important to understand exactly what nicotine is and how it causes harm.

Nicotine is in tobacco cigarettes, but by itself it is not the most damaging ingredient. Tar, carbon monoxide and other dangerous chemicals are chiefly responsible for serious illnesses and death caused by cancer, lung and heart disease.

Public Health England looked closely at nicotine exposure in two landmark evidence reviews.

In their report ‘E-cigarettes: an evidence update,’ scientists found: “EC [E-cigarette] exhalations contained eight times less nicotine than cigarette exhalations. Estimating environmental nicotine exposure, however, has to take into account the fact that side-stream smoke (ie the smoke from the lighted end of the cigarette, which is produced regardless of whether the smoker is puffing or not) accounts for some 85% of passive smoking and there is no side-stream EC vapour. A study measuring nicotine residue on surfaces in houses of smokers and vapers reported only negligible levels from vaping, 169 times lower than from smoking.”

Do Indoor Bans Hurt Vapers?

Many vapers use e-cigarettes as a way of getting nicotine without smoking. Although e-cigarettes are not approved by the FDA as a stop smoking aid, many vapers use the devices to switch.

One of the main arguments in favor of allowing e-cigarette use indoors and in public places is that it can encourage more tobacco users to make the switch to e-cigarettes.

As well as the relative health and cost factors, being indoors is a powerful incentive for smokers that are thinking about ditching tobacco in favor of e-cigs.

After years of huddling in dusty entranceways and freezing cold smoking shelters, they might once again be welcomed back into civil society at the same time as getting a nicotine fix.

This could encourage more people to ditch tobacco, which is a key health policy objective in the United States. But indoor vaping bans would remove this incentive.

Allowing vaping in places where smoking is not permitted could also minimize the discomfort and withdrawal symptoms that vapers experience when they are forced to share a smoking area with tobacco users.

People who have tried to ditch tobacco will know that cigarette cravings are powerful and sometimes mysterious.

Being around other people who smoke - whether it is at home, at work or while out socializing - can be a powerful trigger for smokers that are trying to ditch tobacco.

You may feel a strong temptation to smoke when you are watching someone else smoking or smell the smoke from a cigarette.

Most stop smoking advice will tell you to avoid cigarette smokers if you can, but if you are forced to share a smoking area with tobacco users then this becomes very difficult.